INDIANAPOLIS — There is little question how critical Ryan Kelly is to Duke.

The Blue Devils are 20-1 with him this season and 9-4 without him. They also are 110-14 with Kelly in his four years. His .887 winning percentage is the third-greatest by any Duke player ever.

Kelly, a 6-foot-11 senior forward, may need to deliver more on the offensive end tonight in order for second-seeded Duke to beat third-seeded Michigan State in the Midwest Region semifinal. The game is the marquee event in the Midwest — it may also be the marquee one in the Sweet 16, period — as it features powerhouse schools that have superb coaches in Mike Krzyzewski and Tom Izzo.

“It’s going to be a man’s game,” freshman Duke guard Rasheed Sulaimon said, “and it is going to be a clash of two great programs.”

It’s also a game in which Kelly’s performance bears watching because of his recent struggles. In Duke’s Round of 32 win over Creighton, Kelly missed all five of his shots from the field and scoring one point.

But it’s not all about how many digits Kelly produces in the boxscore. Nix cited Kelly’s intelligence and team play as opposed to simply his scoring. And Krzyzewski praised Kelly’s poise, on-court communication and defensive ability.

Nevertheless, Kelly’s shooting is important. He is a career 46.4-percent shooter from the field and a 38.8 percent marksman from 3-point range. He averaged 13.3 points and 5.4 rebounds this season while sinking 45.9 percent of his shots from long distance.

“He stretches the defense because he can shoot the ball very well,” Payne said.

Kelly missed 13 games in midseason due to a right foot injury suffered on Jan. 8 (Duke was 15-0 when he got hurt). In his return against Miami on March 2 at Cameron Indoor Stadium, he poured in 36 points on 10-for-14 shooting and 7-of-9 from beyond the arc. Kelly was fine in his next two games too, but in his three contests since then (including both NCAA Tournament games), he has shot a combined 6-for-24 and 0-for-10 from deep.

“As far as my shot goes, I’m not worried about that,” Kelly said.

“There was divine intervention when he came back for the first Miami game,” Krzyzewski said. “Since then, his body told him, ‘Hey, I know we’re in March, but your body’s in October.’ Maybe he’s in December now with his body.”

The only Blue Devils in history who have a better career winning percentage than Kelly’s .887 are Shane Battier (.897) and Casey Sanders (.895). Kelly can’t top either one, even if Duke wins it all this season.

Still, third all-time — at Duke — is an eye-opening achievement. Kelly may have to produce more tonight, though, to keep his team’s run, and his Duke career, going for another round.